How would the Second World War change if the Allies had modern E-2 and E-3 airborne-warning aircraft?
Short answerThe Allies would gain overwhelming surveillance and command advantages, likely shortening the European war dramatically by exposing Axis movements and weakening surprise.
NotesDetection and command would matter more than greater aircraft performance alone. Modern airborne radar could reveal large formations, expose moves such as an advance through the Ardennes, and remain exceptionally difficult for early-war fighters to intercept. That information advantage would alter air defense, artillery spotting, operational planning, and the pace of the war.